Dorothy "Dot" is Bob and Tom's mother. In Scoop's Recruit, she joined Robert to run the Bobsville yard office. Just like Robert, Dot calls Bob "Bobby". In Lofty's Comet, Dot says that Bob was always into looking through a telescope when he was young, and she used to always have trouble getting him into bed. Sometimes she joins Robert to help their son with construction jobs. In The Knights of Can-A-Lot, Mr. Bentley called her by her real name Dorothy. Dot and Robert used to live in Bobsville when Bob and Tom were babies and teenagers.